Today wireless devices, such as mobile phones, typically support other wireless technologies such as Wireless Local Area Networks (WLANs), commonly referred to as Wi-Fi, in addition to the cellular standards. As a means to improve the network capacity in future networks, Wi-Fi is intended to be an integral part. That is, Wi-Fi will be regarded as just another radio access technology, so that a connection or handover can be made to Wi-Fi without the user noticing that the service is no longer being carried by 3GPP technologies like WCDMA or LTE.
3GPP Long Term Evolution, LTE, is the fourth-generation mobile communication technologies standard developed within the 3rd Generation Partnership Project, 3GPP, to improve the Universal Mobile Telecommunication System, UMTS, standard to cope with future requirements in terms of improved services such as higher data rates, improved efficiency, and lowered costs. The Universal Terrestrial Radio Access Network, UTRAN, is the radio access network of a UMTS and Evolved UTRAN, E-UTRAN, is the radio access network of an LTE system. In an UTRAN and an E-UTRAN, a User Equipment, UE, is wirelessly connected to a Radio Base Station, RBS, commonly referred to as a NodeB, NB, in UMTS, and as an evolved NodeB, eNB or eNodeB, in LTE. An RBS is a general term for a radio network node capable of transmitting radio signals to a UE and receiving signals transmitted by a UE.
Presently handover between a network using 3GPP technologies and a Wi-Fi network is controlled by the wireless device. This is due to that the Wi-Fi network is still not sufficiently tightly integrated with the cellular networks using 3GPP technologies. However, using Wi-Fi is from a user perspective often preferred, because of the lower cost associated with it. Therefore, a handover is often performed to Wi-Fi as soon as a Wi-Fi network is detected and the signal strength is sufficiently high. Hence, when a wireless device is in range of a Wi-Fi network it will typically connect to this wireless network when the received signal strength indication, RSSI, is sufficiently high, without further analysis.
There are also prior art solutions where an access point gives admission to a device in connection with a handover between cells. As an example, published patent application US2008146240 discloses call admission control providing a method for use in wireless local area network, involving determining whether an access point has sufficient unused bandwidth to handle additional call in response to call admission control request.
Another example of known technique is “A comprehensive resource management framework for next generation wireless networks”, by Jian Ye; Jiongkuan Hou; Papavassiliou S, IEEE TRANSACTIONS ON MOBILE COMPUTING, 2002, Vol. 1, No. 4, pp. 249-264, which is disclosing a method for comprehensive resource management framework in the next generation wireless networks. The document introduces a combined resource management and call admission control scheme which simultaneously considers user mobility and user service type. This solution, takes into account several other functions when performing the admission control, such as probability of an incoming call from an already connected idle wireless device, probability of an incoming HO, etc. This solution is suitable for admission to a wireless network node in a cellular network, where wireless devices are moving between cells.
However, a Wi-Fi network is not necessarily affected by the mobility of devices. The Wi-Fi network often operates as a complement to the cellular network, for offloading traffic in busy areas.
Furthermore, the actual performance which can be supported by a Wi-Fi network might be poor although the predicted performance is high. One example is that the received signal has a very high strength/level and/or quality, but that the data rate that a wireless device gets once connected to the Wi-Fi network is very low. This leaves a high amount of uncertainty to the users, because the Signal Strength Indicator, which is typically displayed in the user interface of the device, will then not correspond to the actual performance. When the wireless device connects or performs handover to Wi-Fi networks which cannot provide a required performance, users of the wireless devices tend to completely turn off Wi-Fi, which of course overturns the idea of Wi-Fi as a means to improve the performance.